The present invention relates to the one lung anesthesia and ventilation arts. It finds particular application to endotracheal tubes having an endobronchial blocker and will be described with particular reference thereto.
Endobronchial or one lung anesthesia is utilized for a variety of surgical procedures when it is necessary to selectively eliminate ventilation to one portion of the lung. There are a few specific indications for utilizing one lung anesthesia. One is to prevent the spill over of secretions or blood from one area of the lung to other non-involved areas during the perioperative period. The incidence of lung infections requiring surgery, also requires isolation of the infected lung utilizing one lung anesthesia. Lung abscesses poses a major problem with a potential for massive intraoperative spillage and contamination of the contralateral lung. A patient with major hemoptysis requiring pulmonary resection is also a candidate for this technique.
A second indication concerns the need to maintain airway continuity to insure the ability to provide positive pressure ventilation. This occurs in the presence of either an acute or chronic bronchopleural fistula or during operative techniques necessitating interruption of the airway to a lung segment. This typically occurs during a sleeve resection of the bronchus.
A third indication, and perhaps the most common indication for using one lung anesthesia, is the ability to provide better surgical exposure and operating conditions. In addition to the above indications used during surgery, several non-surgical applications have been found. Endobronchial intubation has been used to provide selective positive pressure ventilation during acute respiratory failure. This technique is useful in ICU patients with a large chronic bronchopleural fistula or acute pulmonary disease, especially when associated with major differences in compliance between right and left lungs. Additionally, the technique of bronchopulmonary lavage for alveolar proteinosis, bronchiectasis, and other pulmonary diseases requires the use of endobronchial intubation.
A variety of methods and devices exist to isolate a portion of a lung or an entire lung. Several considerations in choosing the appropriate technique include the nature of the operative procedure, preexisting pulmonary pathology, urgency of the situation, anatomical considerations, and experience of the user.
Intraluminal obstruction of the main bronchi or lobar divisions of the airway has been achieved with the use of several devices, including gauze tampons or specially designed balloon-tip catheters. One device is shown in FIG. 1A and is the Magill balloon-tipped bronchial blocker. This device is a long double-lumen catheter. One lumen is used to inflate a cuff on the distal end of the catheter. The second lumen accommodates a stylet during placement and allows suctioning and degassing of the lung distal to the catheter tip. A bronchoscope, passed with the aid of local or general anesthesia, is used to identify the bronchial segment to be blocked. With the aid of a bronchoscope, the blocker is passed into position and the balloon inflated with sufficient volume to hold the catheter in place. With reference to FIG. 1B, once the catheter is in position, the stylet is removed and a standard cuffed endotracheal tube is placed with the cuff inflated to provide additional stability for the blocker. This device has disadvantages that once the blocker is placed and endotracheal intubation is done, it is difficult to reconfirm the existence of the original position. Slippage of the blocker was common with a change in the patient's position, coughing, or surgical manipulation.
Inoue, U.S. Pat. No. 4,453,545 describes an endotracheal tube with movable endobronchial blocker for one lung anesthesia as shown in FIG. 2. The endotracheal tube has a small channel formed within the wall of the endotracheal tube along most of its length. A balloon-tipped catheter is slidably housed in the small channel and can be extended into the main bronchus. This device has a disadvantage in that the channel formed within the wall of the endotracheal tube impinges upon the inner ventilating diameter of the tube. An additional disadvantage is that the endobronchial blocker is a permanent and fixed portion of the apparatus and is not removable, rotatable, or replaceable.
The present invention provides a new and improved endotracheal apparatus and method which overcomes the above-mentioned problems and others.